Anti-inflammatory activities of alkaloids from the mangrove endophytic fungus Phomopsis sp. SYSUQYP-23

Pleosmaranes A-R, Isopimarane and 20-nor Isopimarane Diterpenoids with Anti-inflammatory Activities from the Mangrove Endophytic Fungus Pleosporales sp. HNQQJ-1

Pleosmaranes A-R (1-18), 18 new isopimarane-type diterpenoids, together with four known analogs (19-22), were isolated from the mangrove endophytic fungus Pleosporales sp. HNQQJ-1. Their structures and absolute configurations were established by analysis of their spectroscopic data and electronic circular dichroism (ECD) calculations. Compounds 1-9 possess an unusual aromatic B ring and a 20-nor-isopimarane skeleton. Compounds 15-17 contain a unique 2-oxabicyclo[2.2.2]octane moiety. Compound 18 features an unexpected 2-oxabicyclo[3.2.1]octane moiety. Compounds 8 and 12 exhibited a moderate inhibitory effect against LPS-induced NO production, with IC50 values of 19 and 25 μM, respectively.

New prenylated indole-benzodiazepine-2,5-diones with α-glucosidase inhibitory activities from the mangrove-derived Aspergillus spinosus

Mangrove-derived fungi have been demonstrated to be promising source of structurally diverse and widely active secondary metabolites. During our search for new bioactive compounds, eight new indole-benzodiazepine-2,5-dione derivatives asperdinones A-H (1-8) and two known congeners (9 and 10) were isolated from the culture extracts of the mangrove-derived fungus Aspergillus spinosus WHUF0344 guided by one strain many compounds (OSMAC) and the heteronuclear 1H, 13C single-quantum coherence (HSQC) based small molecule accurate recognition technology (SMART) strategies. The structures and absolute configurations of the new compounds were elucidated by detailed spectroscopic analyze and electronic circular dichroism (ECD) calculations. The putative biosynthetic pathway of these compounds was proposed. Compounds 1-10 were evaluated for their antibacterial and α-glucosidase inhibitory activities. None of compounds showed antibacterial activity. Compounds 2-6 and 8 exhibited moderate inhibitory effects against α-glucosidase with IC50 values in the range of 24.65-312.25 μM. Besides, both 3 and 4 inhibited α-glucosidase variedly. Furthermore, the molecular docking study showed that compounds 2-4 were perfectly docking into the active sites of α-glucosidase. This study not only enriched the chemical diversity of secondary metabolites from the mangrove-derived fungi, but also provided potential hit compounds for further development of α-glucosidase inhibitors.

Metabolites isolated from the mangrove endophytic fungus Didymella sp. CYSK-4 and their cytotoxic activities

Two new 12- or 13- membered-ring macrocyclic alkaloids ascomylactam D and E (1 & 2), and a pair of new enantiomer (+)- and (-)- didymetone (3) were purified from the mangrove endophytic fungus Didymella sp. CYSK-4. Their structures and absolute configurations were determined by extensive spectroscopic analysis, single-crystal X-ray diffraction, ECD and 13C NMR calculations. Compound 2 exhibited significant cytotoxicity against human A549 and KYSE 150 cancer cell lines with IC50 values of 2.8 μM and 5.9 μM, respectively.

Cyclohexenoneterpenes A-J: Cytotoxic meroterpenoids from mangrove-associated fungus Penicillium sp. N-5

Ten previously undescribed meroterpenoids, cyclohexenoneterpenes A-J (1-7, 18-20), together with 10 known analogues (8-17) were isolated from the mangrove-associated fungus Penicillium sp. N-5. Their structures were elucidated on the basis of extensive spectroscopic and mass spectrometric data. The absolute configurations of the undescribed compounds were assigned by electronic circular dichroism calculations, the modified Mosher's method, NMR calculations and DP4+ analysis. In the bioassay, compounds 10, 11, 15, and 20 exhibited cytotoxicities against SNB-19, MDA-MB-231, MDA-MB-435 and HCT-116 cell lines with IC50 values ranging from 1.4 to 19.1 μM.

Mangrove-associated endomycota: diversity and functional significance as a source of novel drug leads

Endophytic fungi are known for their unprecedented ability to produce novel lead compounds of clinical and pharmaceutical importance. This review focuses on the unexplored fungal diversity associated with mangroves, emphasizing their biodiversity, distribution, and methodological approaches targeting isolation, and identification. Also highlights the bioactive compounds reported from the mangrove fungal endophytes. The compounds are categorized according to their reported biological activities including antimicrobial, antioxidant and cytotoxic property. In addition, protein kinase, α-glucosidase, acetylcholinesterase, tyrosinase inhibition, antiangiogenic, DNA-binding affinity, and calcium/potassium channel blocking activity are also reported. Exploration of these endophytes as a source of pharmacologically important compounds will be highly promising in the wake of emerging antibiotic resistance among pathogens. Thus, the aim of this review is to present a detailed report of mangrove derived endophytic fungi and to open an avenue for researchers to discover the possibilities of exploring these hidden mycota in developing novel drug leads.

Fungal Endophytes: Microfactories of Novel Bioactive Compounds with Therapeutic Interventions; A Comprehensive Review on the Biotechnological Developments in the Field of Fungal Endophytic Biology over the Last Decade

The seminal discovery of paclitaxel from endophytic fungus Taxomyces andreanae was a milestone in recognizing the immense potential of endophytic fungi as prolific producers of bioactive secondary metabolites of use in medicine, agriculture, and food industries. Following the discovery of paclitaxel, the research community has intensified efforts to harness endophytic fungi as putative producers of lead molecules with anticancer, anti-inflammatory, antimicrobial, antioxidant, cardio-protective, and immunomodulatory properties. Endophytic fungi have been a valuable source of bioactive compounds over the last three decades. Compounds such as taxol, podophyllotoxin, huperzine, camptothecin, and resveratrol have been effectively isolated and characterized after extraction from endophytic fungi. These findings have expanded the applications of endophytic fungi in medicine and related fields. In the present review, we systematically compile and analyze several important compounds derived from endophytic fungi, encompassing the period from 2011 to 2022. Our systematic approach focuses on elucidating the origins of endophytic fungi, exploring the structural diversity and biological activities exhibited by these compounds, and giving special emphasis to the pharmacological activities and mechanism of action of certain compounds. We highlight the tremendous potential of endophytic fungi as alternate sources of bioactive metabolites, with implications for combating major global diseases. This underscores the significant role that fungi can play in the discovery and development of novel therapeutic agents that address the challenges posed by prevalent diseases worldwide.

Iridoids from Patrinia heterophylla and their anti-inflammatory activity

A phytochemical investigation led to the isolation of five undescribed compounds (1-5) from the methanol extract of the rhizomes and roots of Patrinia heterophylla. The structures and configurations of these compounds were characterized by HRESIMS, ECD, and NMR data analyses. These compounds were assayed for their anti-inflammatory potential using LPS-stimulated BV-2 cells, of which compound 4 showed strong nitric oxide (NO) inhibitory effects with an IC₅₀ of 6.48 μM. The potential anti-inflammatory mechanism was examined utilizing Western blotting and molecular docking. Further in vivo anti-inflammatory experiments revealed that compound 4 inhibited the production of NO and reactive oxygen species in the zebrafish model.

Metabolites With Cytotoxic Activities From the Mangrove Endophytic Fungus Fusarium sp. 2ST2

Two new 3-decalinoyltetramic acid derivatives with peroxide bridge fusarisetins E (1) and F (2), one new chromone fusarimone A (5), two new benzofurans fusarifurans A (9) and B (10), three new isocoumarins fusarimarins A–C (11–13), as well as five known analogues 3, 4, 6–8 and 14 were isolated from mangrove endophytic fungus Fusarium sp. 2ST2. Their structures and absolute configurations were established by spectroscopic analysis, density functional theory-gauge invariant atomic orbital NMR calculation with DP4+ statistical analysis, and electronic circular dichroism calculation. Compounds 1 and 2 showed significant cytotoxicity against human A549 cell lines with IC₅₀ values of 8.7 and 4.3 μM, respectively.

Sesquiterpenoids and furan derivatives from the Orychophragmus violaceus (L.) O.E. Schulz endophytic fungus Irpex lacteus OV38

Nine undescribed compounds, including six tremulane-type sesquiterpenoids, irpexolaceus A-F, one phenolic bisabolane-type sesquiterpenoid, irpexolaceus G, and two furan derivatives, irpexonjust A-B, as well as eight known analogs, were isolated from an endophytic fungus (Irpex lacteus OV38) of Orychophragmus violaceus (L.) O.E. Schulz, a Chinese medicinal and edible plant. The structures of these natural compounds were elucidated based on NMR, HRESIMS, single-crystal X-ray diffraction, and ECD spectroscopic data. Among the tested isolates (50 μg/mL), the inhibitory effects of irpexolaceus A, C, D, F, and G, irpexonjust B, and irpexlacte B against NO release from LPS-induced RAW 264.7 cells were higher than 45%, while irpexlacte C (42.6%), irpexolaceus B (39.6%), irpexonjust A (43.7%), and irpexolaceus E (33.6%) exhibited weaker inhibitory effects on the release of NO.

Secondary metabolites from mangrove-associated fungi: source, chemistry and bioactivities

Covering 1989 to 2020The mangrove forests are a complex ecosystem occurring at tropical and subtropical intertidal estuarine zones and nourish a diverse group of microorganisms including fungi, actinomycetes, bacteria, cyanobacteria, algae, and protozoa. Among the mangrove microbial community, mangrove associated fungi, as the second-largest ecological group of the marine fungi, not only play an essential role in creating and maintaining this biosphere but also represent a rich source of structurally unique and diverse bioactive secondary metabolites, attracting significant attention of organic chemists and pharmacologists. This review summarizes the discovery relating to the source and characteristics of metabolic products isolated from mangrove-associated fungi over the past thirty years (1989-2020). Its emphasis included 1387 new metabolites from 451 papers, focusing on bioactivity and the unique chemical diversity of these natural products.

Biologically Significant and Recently Isolated Alkaloids from Endophytic Fungi

A selection of the established and recently characterized alkaloids from the exploration of plant- and some marine-associated endophytic fungi is reviewed, with reference to alkaloids of biological significance.

Bioactive isocoumarins isolated from a mangrove-derived fungus Penicillium sp. MGP11

Two new isocoumarins penicimarins L-M (1-2), along with seven known analogues (3-9) were isolated from the mangrove-derived fungus Penicillium sp. MGP11. Compounds 1-2 were established by spectroscopic methods and comparison of their circular dichroism (CD) spectra with the literature. All isolated compounds were evaluated for antioxidant and α-glucosidase inhibitory activities. Compound 8 had better antioxidant activity (IC₅₀ = 4.6 μM) than positive control trolox (IC₅₀ = 12.9 μM). Compounds 5, 8 and 9 exhibited α-glucosidase inhibitory activity with the IC₅₀ values of 776.5, 683.7 and 868.7 μM, respectively.

Bioactive sesquiterpene derivatives from mangrove endophytic fungus Phomopsis sp. SYSU-QYP-23: Structures and nitric oxide inhibitory activities

Eight new sesquiterpene derivatives (2, 4-6 and 10-13), along with five known analogues were isolated from the mangrove endophytic fungus Phomopsis sp. SYSU-QYP-23. Their structures of new compounds were established by spectroscopic methods, and the absolute configurations were confirmed by single-crystal X-ray diffraction analysis and comparison of the experimental ECD spectra. The absolute configuration of the side chain in 1 was first defined by modified Mosher's method. Compounds 1-7 showed potent inhibitory activities against nitric oxide (NO) production in lipopolysaccharides (LPS) induced RAW 264.7 cells with IC₅₀ values ranging from 8.6 to 14.5 μM. The molecular docking results implied that the bioactive sesquiterpenes may directly bind with targeting residues in the active cavity of iNOS protein.